Helically shaped lengths of hollow tubing are known. It is further known that a member such as a ball can be disposed in the tubing and caused to traverse same from one end to the other by use of gravity or by selectively moving or rotating the tubing. It is known that a ball constrained to move along a particular path can be caused to impinge upon a pair of normally open contacts at an end of the path and to close them. In this invention, these known structures and techniques have been combined to produce a new type of device which can be used as an amusement for children or as a toy or for purposes of exercise.